Algorithm animation (1/5)

We can watch almost any algorithm's execution by animating it. We choose Closest Pair in the Animation menu, close the W2 Geo-1 window without saving it, and choose again Closest Pair:Plane Sweep from the Operations menu.

Figure 7

The animation of the sweep begins

The idea of the algorithm is to sweep; the plane with a vertical line from left to right and to remember the closest pair of the points to the left of the sweep line. In the Geo - 1 window we see a thick vertical line representing the sweep line; and a line segment connecting the two left-most points, the closest pair; found so far. This is the proper initialization of this algorithm. We step through the algorithm by clicking twice the Continue button in the Animationdialog box.

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